1. Field of the Invention
The present invention relates to methods for making heat dissipation devices, and more particularly to a method for making a heat dissipation device which provides great heat removal capability.
2. Related Art
Electronic devices such as central processing units (CPUs) generate a lot of heat during normal operation. This can deteriorate their operational stability and damage associated electronic devices. Thus the heat must be removed quickly to ensure normal operation. A heat dissipation device is often attached to a top surface of a CPU, to remove heat therefrom.
A conventional heat dissipation device is formed by extrusion, which significantly limits the height of its formed fins. Furthermore, to meet increasing demands for dissipation of ever-increasing amounts of heat, larger and larger heat dissipation devices are being manufactured. This results in excessively heavy heat dissipation devices, and high costs for manufacturers.
To resolve the above-mentioned problems, another kind of heat dissipation device has been developed. The fins of such device are folded from a metal sheet. A chassis in thermal contact with a CPU supports the fins. The device has a large heat dissipation surface area. However, because the fins are folded from a metal sheet, a cooling fan cannot be easily and securely attached to the fins. The device generally removes heat without the benefit of a fan. Furthermore, the chassis of the heat dissipation device is generally a thin metal plate. This limits heat conduction, thereby reducing the efficiency of heat transfer. Oftentimes, the device cannot satisfactorily remove heat from the CPU.
In other conventional heat dissipation devices, a metal block is attached to a bottom of a chassis of the device. This increases a thickness of the chassis engaging with the heat-generating electronic device, and thereby attains higher heat conduction. However, the extra materials required increase manufacturing costs. Furthermore, gaps exist between the metal block and the chassis, thereby retarding heat transfer. Oftentimes, such device cannot attain the required level of heat conduction.
A method for making an improved heat dissipation device which overcomes the above-mentioned problems is strongly desired.
Accordingly, an object of the present invention is to provide a method for making a heat dissipation device which has great heat removal capability.
Another object of the present invention is to provide a simple, efficient and economical method for making a heat dissipation device.
To achieve the above-mentioned objects, a method for making a heat dissipation device in accordance with the present invention comprises the steps of: providing a metal plate and a fin member, bending the metal plate to form a body, and attaching the fin member to the body. The metal plate comprises a central portion and a pair of end portions. The central portion is thicker than the end portions. The body comprises a chassis originating from the central portion of the metal plate, and a pair of side walls originating from the end portions of the metal plate. The fin member is attached to the chassis between the side walls.